A natural history of consent
The third and last part of a mini-series on the evolutionary psychology of sexual coercion. The first two posts were written from the female side. This post is about the male perspective.
In 2000, the book A Natural History of Rape by Randy Thornhill and Craig Palmer was published. Explaining rape as natural was so outrageous that it even reached my corner of the world. I remember the angry reactions and satire cartoons the book generated.
Many years later, I actually read the book. I didn't find it outrageous. But I also didn't find it very interesting. Basically, the book only said that rape might have been adaptive. Why wouldn't it be? If rape was a kind of maladaptive disease, why would it then occur all over the world? It is possible that there are a few small-scale societies where rape doesn't occur. But the vast majority of human populations, across cultures, recognize rape as a fact. This fact alone contradicts the "disease" notion of rape rather effectively. I understand that people prefer to see sexual coercion as a social disease to which there could be a simple cure. But that kind of thinking is more wishful than serious. If contradicting such wishful thinking was the objective, Randall and Thornhill succeeded. But it didn't help me much, because I didn't believe such things from the beginning.
I think the question Why do men rape? is just too simple. Men rape for the same reason that they steal: They do it in order to take what they want and show domination, in various proportions. Instead, I think the interesting questions are Why do men not rape? and Why do men not steal? Stealing and coercion are a basic tenet of nature. How come that humans managed to suspend those simple laws of nature more than any other animal? How come we tamed ourselves to inhibit our natural selfish impulses so we could instead form self-interested groups consisting of millions of people? The fact that humans are a part of nature is just mundane. The interesting question is how we could ever escape as far as we have from the basic laws of nature.
A consent preference
Obviously, many men are prepared to commit rape. Otherwise the phenomenon wouldn't persistently occur all over the world. In When Men Behave Badly, David Buss cites two studies that asked people about their attitudes to rape. Men were asked if they would commit rape if they were certain that they could get away with it. 27-35 percent indicated some probability that they could commit rape under such ideal conditions. The rest did not think there could be any such probability.1 Interestingly, when researchers asked women how many men they guessed would commit rape if they thought they could get away with it, the average answer was 37 percent. It all implies that both men and women think that most men would actually not commit rape, even under "ideal" conditions.2
I think that most of all, signs of a male consent preference can be seen in pornography. People seldom watch pornography for moral reasons. They watch what turns them on the most. And men who watch pornography watch depictions of non-consensual sex much less often than women who watch pornography.3
Men do not only like to have sex with consenting partners. They also commonly obsess over inducing pleasure in their partners. In a study of people's sexual fantasies, men’s fantasies were slightly more likely to include their partner's sexual pleasure than their own. Women's fantasies were significantly more likely to include their own sexual pleasure than their partner's.4
From this we can conclude that there is a strong male preference for having sex with consenting women who are enjoying the experience. This preference is in no way universal or exclusive; if it was, rape wouldn't have been a thing. But it implies that men have evolved away from an indiscriminate desire to grab every reproductive opportunity.
Enter self-domestication
I have previously written about the self-domestication theory, described by Richard Wrangham and others5. The self-domestication theory says that beta-males were able to form coalitions against alpha males who acted too dominantly. The beta males simply subdued or killed off men who took more than what was considered their fair share of resources and women.
According to Richard Wrangham, the self-domestication process had very deep consequences for the human race. If formed our anatomy and selected for more neotenous traits in males and females: Smaller bodies, flatter faces, less anatomical differences between the sexes and smaller brains.6 It made people less spontaneously aggressive and thereby allowed us to form bigger groups. In one sentence, it made humanity into what it is today: a species with an intellectual capacity inherited from the apes, but with a capacity for cooperation approaching the ants.
The self-domestication process made people, especially males, less aggressive. Thereby it almost certainly made male sexuality less aggressive. We don't know exactly why humans self-domesticated. It might have been an evolutionary process counteracting aggression in general, with reduced sexual aggression only as a by-product. However, I think the fact that males seem to have a stronger sexual aversion against violence and coercion compared to females is somehow telling. It indicates that there are indeed special adaptations that hold men back from acting violently and coercively towards women.
Sneaky consent
Except for the general self-domestication principle, there are two possible reasons that males who avoid sexual coercion would be selected for.
The happy-wife-happy-life principle. Although a man can force himself on his wife, doing so will not automatically give him more children. Being tyrannical and mean to one's wives is one possible successful reproductive strategy. Being part of a good team is another.
Men who sought to please their partners were much better at initiating and maintaining illicit affairs.
I think argument 2 is stronger than argument 1. In societies where men own women, treating those women well is not obviously reproductively beneficial. But in an environment where men guard women, having a secret affair with a willing woman is definitely a better strategy than raping an unwilling woman. It is easy to imagine the fate of a rapist who tries to drag away a woman who screams for someone to help her. And the success of the seducer who comes with gifts and makes the same woman act very discreetly. It is not unlikely that men have evolved a desire to please women and seek their consent at least partially because such generous and considerate men had more successful affairs than more selfish men. Genetic tests show that a few percent of children in primitive societies tend to have the “wrong” fathers, which is enough to make seducer genes successful over time.78
The principle for sneaky seduction seems to be old. Chimpanzees and bonobos kind of have affairs: They meet out of sight of higher-ranking individuals. They agree on a meeting spot and take precautions not to be seen together. Pleasing a female chimpanzee or bonobo chimpanzee is not difficult at all - they are heavily into sexual variety.
Female chimpanzees can afford to be nymphomaniacs since they raise their kids themselves. For human females the equation looks quite different since they are significantly more dependent on male investment and vulnerable to male violence. An erring female is at risk of losing her and her childrens’ provider and to provoke lethal violence from her rightful owner. There is a high barrier to having illicit affairs with her. But not an insurmountable one. Males who knew how to please females could get reproductive opportunities for less investment. They could also skip some of the struggle between men over women and instead make secret pacts directly with women.
Only rape your own
Over many generations, evolution muted the male instinct to take every reproductive opportunity quite a bit. But not totally. Sexual coercion exists to this day.
However, as I wrote in my post Rape - a crime enabled by politeness, most rapists are not violent. It is so rare that a man physically assaults a woman in a dark alley that it becomes newsworthy stuff when it happens. The typical rapist is a man who finds himself alone with a woman and just takes advantage of the situation.
I think that kind of behavior is adaptive. Men who violently assaulted women who were not theirs risked arousing the rage of other men. Men who ignored the interests of women they controlled faced few consequences at all.
All-in-all, violent rapists were probably selected against in a general self-domestication process. Considerate lovers were selected for on the illicit market and, to some degree, within cooperative marriages. The pressures were not strong enough to completely counteract the general tendency of individuals to take what they want, when they can. But they were strong enough to create a mixture of cooperativeness and selfishness.
It might seem ironic that men, at least in some respects, actually seem better adapted to avoid rape than women. But I think it makes sense. When it comes to sexual coercion, males have the agency: By definition, women couldn't decide whether to get raped or not. They could take certain precautions, but those were never completely effective. For a woman, dealing with the fact that rape sometimes occurred was more efficient than feeling strongly against all kinds of rape. By contrast, men actually had the agency to decide when to rape or not. For that reason, it makes sense that men evolved mechanisms to abstain from committing rape while women evolved mechanisms to handle the rapes that inevitably happened. The decision was theirs, and those who made the right decisions did better in the long run.
David Buss, When Men Behave Badly, 2021, chapter 7, 60 percent
David Buss, When Men Behave Badly, 2021, chapter 8, 72 percent
Seth-Stephen Davidowitz, Everybody Lies: Big Data, New Data, and What the Internet Can Tell Us about Who We Really Are, 2017, chapter 4, 31%, https://www.vox.com/conversations/2017/6/27/15873072/google-porn-addiction-america-everybody-lies
Eileen Zurbriggen, Megan R. Yost, Power, Desire, and Pleasure in Sexual Fantasies, 2004, page 292 Sci-hub link
Richard Wrangham, The Goodness Paradox, 2019
Richard Wrangham, The Goodness Paradox, 2019, chapter 3, 18 percent
see Brooke A. Scelza et al, High rate of extrapair paternity in a human population demonstrates diversity in human reproductive strategies, 2020, Link
In 1975, James Neel and Kenneth Weiss estimated that 9 percent of children in a studied Yanomamö population were not the biological children of their social fathers. James V Neel and Kenneth M Weiss, The Genetic Structure of a Tribal Population, the Yanomama Indians, 1975, Link, Sci-hub link
Millennia of adaptation to make men non-rapey is not enough for the toxic masculinity movement.
_In a meta-study of people's sexual fantasies, women's fantasies were significantly more likely to include their own sexual pleasure than their partner's. Men’s fantasies were slightly more likely to include another person's sexual pleasure than their own_
I was interested to read more about this, but I read through the Henning and Leitenberg reference and could not find this claim anywhere. Can you provide a pointer?
I see on page 481, Henning and Leitenberg report that men are more likely to imagine being active performers, while women are more likely to imagine being passive recipients—but that seems to me to be a somewhat different claim.